A modular system for cover frames

Abstract: A modular system for cover frames to be mounted about adjoining boxes for mains switches and mains outlets. The manufacture of combination frames is avoided by using a rectangular cover frame dimensioned to enclose a box for a mains switch or a mains outlet. The cover frame is provided with opposing outer edge portions, forming at least one bar which may be separated from the rest of the cover frame. In addition to rendering the use of special combination frames superfluous when several closely interspaced switches and outlet are needed, the described cover frame comply with several national, European standard specifications as well as market related specifications.

Description: The present invention relates to a modular system for cover frames to be mounted about adjoining boxes for mains switches and mains outlets, wherein a rectangular cover frame is used, dimensioned to enclose a box for a mains switch or a mains outlet. Cover frames (escutcheon plates) are mounted on the front face of the completely installed and electrically connected switch, outlet or the like arranged in a mounting box in a wall or in a cable duct, and the purposes of the cover frame include covering and thereby protecting the electric installation and forming a transition from wall to switch. Moreover, for aesthetic reasons, the design of the cover frame should fit in with the surroundings. Cover frames for mains switches and mains outlets are obtainable in many different designs. In a typical electric installation one, two, three or four switches and outlets are needed arranged side by side or one above the other. Prior art switches are enclosed by single cover frames, double, triple or quadruple cover frames, respectively (also named combination frames). Expensive tools are needed for the manufacture of each type of frame and it is therefore of considerable economic advantage to limit the number of different frame types. Norwegian publication No. 151.989 discloses how to limit the number of combination frames by forming a dismountable separation member which can divide a combination frame in many different ways and thereby make room for inserts of various kinds. Consequently, the number of different frame embodiments is limited to a certain extent, but frames of different lengths still have to be manufactured. Furthermore, a modular cover frame system is known, forming combination frames by combining a plurality of I-shaped intermediaries and two end sections being essentially U-shaped and provided with rectangular corners. DE-A-3129061 discloses a rectangular cover frame for mounting around a socket. The cover frame includes outer edge portions which form bars which can be separated from the rest of the frame. To some extent, the structure and dimensioning of electric devices is determined by a number of standards, regulations, and market-related demands to electric installations. It is, thus, required that the cover frame about boxes for mains switches and mains outlets measures at least 80 x 80 mm for a single switch. Moreover, it is restricted how closely interspaced an alignment of switches or outlets may be. According to the basic standards in a number of countries, the minimum centre distance (i.e. the distance centre to centre) between boxes for mains switches and mains outlets should be at least 71 mm, while a centre distance of 57 mm is used in some other countries. The object of the invention is to provide a modular system making it possible to manufacture a single cover frame instead of a number of variants, thus, rendering the manufacture of combination frames superfluous. The cover frame should be usable for both the above centre distances of 71 mm and 57 mm. This object is obtained by a modular system of cover frames for mounting about adjoining boxes for mains switches and mains outlets or the like, wherein each cover frame is substantially rectangular and dimensioned to enclose the box and is provided with opposing outer edge portions, forming at least one bar which may be separated from the remaining cover frame to enable two cover frames to be arranged adjacently, wherein each cover frame is an escutcheon plate and has an opening suitable for receiving a switch key such that each cover frame is capable of being mounted on the front face of a completely installed and electrically connected mains switch, mains outlet or the like. A particular advantage is that it is possible to mount an arbitrary number of cover frames about an alignment of boxes for mains switches and mains outlets being mounted with a given centre distance by separating and removing a "bar" or in other words, an edge portion at the side edge of the cover frames adjacent a succeeding cover frame, as it will be evident from the subsequent detailed description. Furthermore, it has proved particularly advantageous to use a square cover frame having a side length of 85 mm with the above standard centre distances of 57 mm and 71 mm, respectively, as a number of bars of width of 7 mm or possibly 14 mm allows compensation for the difference in dimensions. The cover frame according to the invention, thus, complies with the European as well as certain national standard demands to the distance between boxes for mains switches and mains outlets. The invention is described in greater detail in the following with reference to the particularly preferred embodiments and accompanying drawings, in which Figure 1 shows an example of a preferred embodiment of a cover frame according to the invention, Figure 2 shows a second example of a preferred embodiment of a cover frame according to the invention, Figures 3 to 5 shows an alignment of adjacently mounted cover frames in various embodiments according to the invention for complying with various standards, Figure 6 and Figure 7 show two examples of cover frames as shown in Figure 1 mounted in a vertical arrangement, as it is typically in homes, Figure 8 is a sectional view through a cover frame as shown in Figure 1, Figure 9 is a sectional view through a second embodiment of a cover frame as shown in Figure 1, Figure 10 is an enlarged, sectional view through an example of an embodiment of a groove in a cover frame, Figure 11 shows a third embodiment of a cover frame according to the invention, and Figure 12 to 16 illustrate a fourth embodiment of a cover frame (escutcheon plate) according to the invention as well as some combination possibilities. The cover frame shown in Figure 1 comprises a cover plate, (hereinafter called "frame"), 10 which is essentially square and measures 85 mm by 85 mm in a particularly advantageous embodiment. The frame encloses an essentially square opening or notch 20, which may receive a switch key on a switch mounted in a mounting box or in a cable duct. In a well-known manner, e.g. by means of clip-on means, the frame is intended to be mounted on the front of the completely mounted and electrically connected switch or outlet. A deep groove 12 is provided along both side edges, and as indicated by means of the dotted line 14, possibly two additional grooves make it easy for an electrician to remove one or two (or more, if necessary) of the outer edge portions 16, 18, (hereinafter called "bars"). As a result, two cover frames 10 may be arranged adjacently about two boxes for mains switches and mains outlets mounted with a centre distance of 71 mm according to the CEE standard or with the centre distance of 57 mm used in some countries, such as France. Figure 2 illustrates a second embodiment in principle being essentially identical to the embodiment shown in Figure 1 except for the rounded corners. In a preferred embodiment, two grooves 12 are formed along the upper and lower edge and preferably spaced 14 mm therefrom, each said grooves defining a bar 16 intended to be separated (e.g. broken off) from the remaining cover frame. In other embodiments of the cover frame, for instance two, three or four bars may be provided at each edge, said bar having a width of e.g. 3.5 mm, 7 and/or 14 mm. Figure 3 shows an example of an alignment of switches provided with switch keys 20 and plug outlets provided with outlet taps 22 having four frames 10 mounted so that the centre distance between two adjacent switches or outlets is 71 mm. When using four cover frames as shown in Figure 1, measuring 85 mm by 85 mm and a bar of 7 mm, a bar has to be broken off both frame sides, where a cover frame 10 adjoins another cover frame, as shown in Figure 3. When using a cover frame as shown in Figure 2 having a bar of 14 mm, only one bar of the frame side adjacent another cover frame 19 is to be broken off. It should be stressed that the frame shown in Figure 2 preferably has a square section 20, whereby it can be turned, as shown in Figure 1 and in Figure 2. When using the same cover frame having a bar of 7 mm at locations using a centre distance of 57 mm as standard between two switches, two bars are broken off from both frame sides, where a cover frame 10 adjoins another cover frame, as shown in Figure 4. In the embodiment having a bar of 14 mm, one bar is broken off from both frame sides, where a cover frame 10 adjoins another cover frame. Naturally, the standard frame shown in Figure 1 may also be used as shown in Figure 5, in which three standard frames are mounted in alignment and no bars are broken off, i.e. having a centre distance of 85 mm. In Figures 6 and 7, corresponding examples of four frames of the type shown in Figure 1 are arranged one above the other with a centre distance of 57 mm and 71 mm, respectively. The embodiments shown in Figures 2, 6, and 7 are preferably used for wiring in homes, while the embodiment shown in Figures 1, 3, 4, and 5 are intended for offices, in particular. Provided the cover frame 10 as shown in Figures 1 and 2 is formed with a square section 20, the same frame may be used for mounting as shown in Figures 3, 4, and 5 as well as for vertical mounting as shown in Figures 6 and 7. In a preferred embodiment, the complete cover frame 10 with the bars is formed all in one piece, for instance by moulding or compression moulding. If desired, the moulding can be carried out in two steps with two different plastics materials to enable a subsequent separation of one or more bars. One or more grooves may be formed simultaneously during moulding, said grooves defining the line(s) of separation, and preferably being so deep that it is easy for the electrician to remove one or more bars, preferably without using any tools. However, it is within the scope of the invention to use tools to a small extent, such as a knife for separating the bars from the cover frame 10. Figure 8 and 9 are sectional views through examples of two typical embodiments of the cover frame. The grooves 12, 14 are merely indicated by means of thin, dotted lines. Figure 8 illustrates an example of an embodiment provided with a stepped bar. The upper face of the cover frame may have many different geometrical shapes. However, except for the grooves 12, 14, it is essentially plane, possibly slightly curved in horizontal and/or in vertical direction, when arranged on a vertical wall, or slightly pyramidal, and normally having an essentially smooth, matt or shiny surface being easy to keep clean. The groove may be shaped as a continuous, deep groove, and if desired, may be completely or partially filled with a filling material, such as a soft plastics which do not hinder the separation. The groove may also be composed of a line of perforations. As shown on the Figure, the groove may be formed on the front, and completely filled, or covered by a trim strip. It is within the scope of the invention to form the groove on the back of the cover frame, whereby the front has a smooth surface regardless of the number of remaining bars. In cross-section, the groove may likewise be shaped in different ways, for instance V-shaped or with essentially vertical side and a horizontal or curved bottom. In yet another embodiment, the grooves 12 are formed on the front as well as on the back of the standard frame. An enlarged section thereof being shown in Figure 10,. As a result, a comparatively small, aesthetically designed groove may be provided on the front, the depth thereof being such that said groove may cover any flashes after a bar has been broken off. A deeper groove may be provided on the back to ensure easy separation. In another embodiment, the cover frame and the bars are manufactured individually, whereafter the sections are assembled at the factory with suitable means, such as clip-on means intended therefor, by adhesion or by moulding in such a manner that a subsequent separation may be performed, when the cover frame is mounted on the site of application. Figure 11 shows yet another embodiment of the cover frame having a square opening 20, the cover plate with bar being rectangular (non-squared) and provided with grooves 12,13,14 along each side edge. As the cover frame with the square opening can be turned 90°, the cover frame can be adapted to comply with several different demands as to the centre distances between adjacent switches and outlets by choosing suitable bar widths. Finally, Figure 12 shows an example of an embodiment provided with a stepped bar being 14 mm wide along the upper and lower edges of the cover frame, and a rectangular opening for a switch key. Figure 13 is an example of two cover frames of Figure 12 arranged side by side. Figures 14, 15, and 16 show examples of two cover frames arranged one above the other at a centre distance of 85 mm, 71 mm, and 57 mm, respectively. It is evident the invention may be varied in many ways with the scope of the attached claims. The number and width(s) of the bar(s) formed by means of grooves along one or more of the side edges for separation from the rest of the cover frame may be altered. Moreover, the cover frame 10 may be rectangular as well as square and provided with a rectangular as well as a square opening 20.

Claims: A modular system of cover frames (10) for mounting about adjoining boxes for mains switches and mains outlets or the like, wherein each cover frame is substantially rectangular and dimensioned to enclose the box and is provided with opposing outer edge portions, forming at least one bar (16,18) which may be separated from the remaining cover frame to enable two cover frames (10) to be arranged adjacently, characterised in that each cover frame (10) is an escutcheon plate and has an opening (20) suitable for receiving a switch key such that each cover frame (10) is capable of being mounted on the front face of a completely installed and electrically connected mains switch, mains outlet or the like. A modular system according to claim 1, wherein the cover frame is provided with opposing side sections, each section forming at least one bar (16,18) separable from the remaining cover frame, and/or that the cover frame is provided with upper and lower edge portions, each forming at least one bar (16,18) separable from the remaining cover frame. A modular system according to claim 1 or 2, wherein the cover frame opening (20) is square. A modular system according to one or more of the preceding claims, wherein the cover frame is provided with grooves (12,14) indicating the lines of separation between the detachable bars (16,18) and the remaining cover frame. A modular system according to claim 4, wherein the depth of the grooves and the remaining wall thickness allow the bars (16,18) to be broken off without using any tools. A modular system according to claim 4, wherein the grooves (12,14) are formed on the front and/or on the back of the cover frame. A modular system according to one or more of the preceding claims, wherein the cover frame is square. A modular system according to one or more of the preceding claims, wherein the cover frame and the bars (16,18) are moulded or pressed as an integrated piece. A modular system according to one or more of the preceding claims, wherein the bars and remaining part of the cover frame is moulded or pressed as separate parts. A modular system according to one or more of the preceding claims, wherein the cover frame including the bars (16,18) is 85 mm long and that each separable bar (16,18) is 7 mm or 14 mm long.

Inventors: MADSEN KAJ FISCHER, MADSEN, KAJ FISCHER
Applicants: LK AS, LK A/S
Application year: 1994
Main classification: H02B1
IPC codes: H02G3